The need for new approaches to analog design, in general, arises as a result of the general scaling trends in semiconductor integrated circuit technology. The reason is that technology scaling is generally driven by the need for improved digital integrated circuits, which constitute the majority of circuits in the microelectronics and computer industries. However, scaling generally makes analog design more challenging. For example, digital scaling requires downscaling power supply voltages (for improved reliability and power dissipation), but this can significantly hinder the performance of analog circuits.
From another perspective, although scaling generally means reduced implementation areas for digital circuits (due to the reduction in transistor dimensions) the reduction in analog circuit implementation area (for a given set of performance requirements) is not as significant. Hence, the gains from scaling are sometimes masked in relation to analog integrated circuits.
One option to take advantage of scaling is to use digital or mixed digital/analog solutions rather than typical all-analog solutions for certain circuits. A typically all-analog circuit ripe for re-implementation is a DC voltage generator.